Compressor



Jan. 18, 1927. 1,614,481

J. B. MCMULLEN v COMPRESSOR Filed August 5. 1926 4 sheets-sheet 1 Sme/what.: y Josepf/flullen as @mb 151.4;4-8-1 Jano 9 J B` MGMULLEN COMPRESSOR Filed August 5. 1926 4 Sheets-Sheet 5 Jmmlm,

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UNITED STATES OF BALTIMORE, MARYLAND.

PATENT OFFICE.

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Application les! August 5,

The invention relatesl to compressors of a type adaptable to refrigerators and has as an object the provision of a compressor having rotating cylinders and Apistons in whichA the pistons reciprocate in the cylinders, which parts are enclosed in a gas-tight casing.

A further', object of the invention is to provide means for preserving the relation of the pistons to the reciprocation-causing means.

A further object of the invention is to provide means for withdrawing any gas which may lind its way into -the cylinder casing.

A further object of the invention is to provide a compressor having means to seal the shaft against the leakage of gas therealong.

A further object of the invention is to provide a compressor having no movable valves.

A further object of the invention is lto provide means forlubricating the pistons inthe cylinders.

Further objects will appear from the following description when read in connection with the accompanying drawings showing illustrative embodiments of the invention, and wherein: 1

Fig. 1 is a side elevation with the cover of the casing removed;

Fig. 2 is a vertical section on line 2-2 of Filg?. l;

ig. 3 is a view corresponding to Fig. 1 showing a modied form;

F Fig. 4 is a vertical section on line 4.-4 of Fig. 5 is an elevation corresponding -to Fig. 1 partly in section on line 5-5 of Fig. 6 showing a modified form of cylindermember and showing the inlet and outlet ports;

gig. 6 is a section on line 6-6 of Fig. 5;l an

Fig. 7 is a side elevation partly broken away showing the compressor assembled with the motor.

As shown in Figs. 1 and 2, the device colnprises a casing 10 having a cover 11, the casing comprising a base 12 having an annular ring 13 preferably east integral there- 1926. Serial No. 127,332.

with, and a side plate 14 shown as formed integral with a hub 15.

Revolving upon the hub 15 there is shown an annular member 16 having a plurality vof cylinders formed therein and provided 17 forming a closure for one end the clinderakeach of the cylinders being provi ed with a 'port 18 through the ring 17.

There are shown in the embodiment illustrated, four cylinders formed in the member 16 but it will be understood that a greater or less number may be utilized.

To cause revolution of the member 16 upon the hub 15, there is shown a disc 19 ri idly securedto the end of the driving sha 20, which shaft is shown as journalled in -hub 15, bearing metal bushings 21, 22, being rovided in which the shaft 20 rotates. Ll'he driving force of the disc 19 is desirably applied to the member 16 by means of lugs 23 projecting from the member 16 and extending upon each side of a projection 24 carried by the disc.

To cause reciprocation of the pistons 25 in the cylinders, there is shown a disc 26 eccentricall mounted upon a stub shaft 27 having a s oulder bearing against the inner side of the cover 11 and secured therein by means of a nut 28. One of the pistons 25 isshown as held in fixed relation to the center of shaft 27by means of an arm 29 integral with the disc 26 and the remaining pistons 25 are preserved in this relation by means of links pivotally attached to the disc 26 upon studs 3l formed upon the disc 26. The ends of each of the links 30 and of the arm 29 are pivotally secured to the pistons 25 by means of pins 32 rigidly secured to the pistons 25. y

An important feature of the invention is shown by the provision of the rigid arm 29 for one of the pistons and the links 30 for the remaining pistons. It will be seen that if each of the pistons 25 were connected to the dise 26 by links in pivotal arrangement with the parts at each end, there would be a possible motion of the disc 26 independently of the rotation of the member 16, by means of which motion the pistons could with a rin of each og be moved in um cylinders independenu Aof the rotation of the member 16 thus 'ng possible an en ment of the ends of thev istons with e Aclosed ends of the cyliners. B the arrangement shown revolution of t e part 16 wi l cause a reciprocation of the silsntons in the cylinders.

To a 't to the cylinders gas or air to be com ressed, there isshown a groove 33 in.

' and 35 aremore clearly indicated in the modified form of Fig. 5, which modification introduces a modification of the grooves.

From the dotted lines .of Fig. 1, it will be seen that one of the pistons 25 is 'at the inner limit f its travel in the position at the top of this figure, Ifrom which point the piston begins to leave the bottom of the cylinder and almost immediately its port 18 is uncovered by the intake groove 33, permittin the continued rotation of. the cylinder wit outward travel of the piston 25 to draw in air or gas to be compressed until the out- Ward limit of travel is reached in the osition shown by the lower piston 'in sai iigure, at which point the piston begins its inward travel with compression of the contents of the cylinder, which compression continues unrelieved through a rotation of substantially90 to the osition shown of the piston at the left in ig. 1 when the outlet groove 35 is uncovered, whereupon continuedl inward motion of the piston will be accompanied by flow of compressed as or air into the groove 35 and out of the pipe 36.

As a result of this action and when four pistons are used, there will at all times be one cylinder delivering compressed gas to the groove 35 resulting in a continuous iow of compressed Huid thereby avoiding the pulsation of pressure which results from single cylinder compressors heretofore in use.

The reci rocation of the pistons 25 in the c linders 1s guided through a portion of t e travel in the cylinders by the entry of ins 32 in slots 37 1n a wall of the cylinder. t will be obvious that the diameter of member 16 can be increased to such an extent by enlargement of the casing that the pins may be at all times present in the slots 37 for complete guidance of the pistons axially of the cylinders.

To lubricate the parts shown, there is shown a illing pipe 38 closed by means of walls of the member 16, which passages open into the cylinders.

In the form shown in Figs. 1 and 2, oil from the inner wall -of the member 16 will y ain access to an annular groove 47 in the ub 15 to the space about the shaft 20 throu h passage 48 and through passage-49 out o? the space about the shaft 20 to the surface of the hub 15.

The casing of the compressor can be made gas-tight and it is important in the use of the device with refrigerant compressors in which the gas is often corrosive in character that gas be not allowed to escapa from the casing. A Almost unavoidably some compressed gas will escape from the cylinders to the interior of the casing. To remove such gas, there is shown a pipe 50 in communication with the interior of the casing discharging to the inlet pipe 34, which pipe will be under rarefaction ue to the suctlon of the c. linders during their intake action,l

where y any gas present in the casing will be led into the intake and `removed from the casing.

In the form of the device shown in Figs. 3 and 4, reciprocationof the pistons in the cylinders is caused by means of shoes 51 slidin upon the interior of ring 13 and pre'- serve in contact with the surface of the ring by means of flan es 52, 53, overhanging the shoes 5 1. Each s oe 51 is shown as pivotally connected to the pistons 25 by means of Eins 54. lIn this form of the device, a modied form of means for removing the gasl from the interior of the cylinder is shown in the form of a pipe 55 communicating with a passage in the hub 15 which in turn communicates with the space about the shaft 20. It will be understoodv that this form of gas removal may be utilized with the form of Figs. 1 and 2. In- Fig. 4, the lubricationintroducing pipe 38 is shown in dotted lines as turned downward for-drainage of the oil from the casing.

In the form ofthe device shown in Figs. 5 and 6, the member 16 carrying the cylinders is provided as an annular ring 56 having the cylinders 57 projecting therefrom in spoke-like relation thereto. In this form of the device also, each of the pistons 25 is shown as provided with a rib 58 reciprocating in slots 59 in the walls of the cylinders.

In this lform of the invention also, the

- cylinders 57 are o'set upon the annular member 56 to bring the ports 18 at one side of the cylinders thereby providinga greater surface between said ports and the inner end of hub 15' to provide greater resistance to leakage ofthe compressed gas into the casing. In this form of the device also the ring 13 is made integral with the disc 14 and the hub 15.

An vadditional feature of the invention is shown in Figure 6 in the form of means to seal the space about the shaft 20 against leakage of gas in the form of annular grooves in the surface of the shaft 20 and of means 61 to feed grease to this space under the constant pressure of spring 62. Heavy grease fed to the space about the shaft 20 under this constant pressure will be squeezed into grooves 60 thereby roviding a series of tongues of grease projecting into these grooves to assist in reventing the passage of gas along the sur ace of the shaft 20.

In Figure 7 there is shown a check valve in the outlet pipe adapted to close when lthe pressure in the receptacle containing compressed air or gas exceeds that in the compression cylinders of the pum as when the pump is at rest, to prevent liackpressure causing gas to leak into the casing of the pump.

In the assembly shown in Fig. 7, bed plate 63 is shown desirabl mounted upon resilient blocks 64, 65 and1 clamped thereagainst through the medium of resilient blocks 66, 67, by means of hold-down bolts 68, 69. Upon the bed plate 63 the hub 15 is shown as bolted by means of hold-down bolts and a motor 71 is also secured to the bed plate as by means of hold-down bolts 72, a universal joint 73 providing drive from the motor 71 to the shaft 20.

The operation of the device will be clear from the above description and it will be seen that a compressor which is simple to manufacture is provided and one which will provide a steady flow of compressed gas and which may be run for long periods of time without attention, there being few wearing parts and no movable valves.

Minor changes may be made in the physical embodiment of the invention within the scope of the appended claims without departing from the spirit thereof.

I claim:

1. A compressor comprising in combination, a casing having an inwardly projecting hub, said hub having inlet and outlet grooves and inlet and outlet passages in communication with said grooves, a member having a cylinder revoluble in said casing upon said hub,'said cylinder having a port in the surface thereof bearing upon said hub, said port being in communication with said grooves in turn upon revolution of the member, a

shaft journalled in said hub, means upon' said shaft to cause revolution of said member, a piston 1n said cyllnder, means 1n said casing revolving eccentrically with respect to said hub and connected with said piston whereby to cause reciprocation of the piston upon revolution of the member.

2. A compressor comprising. in combination, a casing having an inwardly projecting hub provided with inlet and out et passages and with circumferential grooves in communication with the respective passages each groove having a substantial extent, a member having a cylinder revoluble in said casin upon said hub and a ort placing said cy inder in communicatlon with said grooves successively, a drive shaft to cause revolution of said member, a piston in said cylinder, means in said casing mounted to revolve eccentrically with respect to said hub and connected to said piston to cause reciprocation thereof during revolution of said member, the location and extent of said grooves being such as to place said cylinder in communication with the intake passage during substantially all of the intake stroke of the piston and with said outlet passage during substantially all of the compressiony stroke thereof.

3. A compressor comprising in combination a casing, a hub projecting inwardly thereof having inlet and outlet grooves and passages in communication therewith, inlet and outlet conduits in communication with said .as-

sages, means placing the inlet'conduit lut-o.

communication with the interior of the casing at a point removed from the lubricated surfaces thereof to withdraw gas from the interior of the casing, a member carrying a cylinder mounted for revolution upon said hub, said cylinder having a port adapted to come into registry alternately with said grooves upon revolution of the member, a shaft journalled in the hub, means carried by the shaft for causing revolution of the member, means mounted for revolution in the casing eccentrically of said shaft, a piston adapted to reciprocate in the cylinder and connected to said last named means whereby revolution of the member may cause reciproca-tion of the piston.

4. A compressor'comprising in combination, a casing having a hub projecting interiorly thereof and having inlet and outlet grooves and inlet and outlet passages connected with said grooves, a member mounted for revolution upon said hub within the casing carrying a plurality of cylinders, said cylinders having ports adapted to communicate in turn with said grooves, a flange carried by said member adapted to intercept oil u on the wall of said member, said cylinders aving passages opening upon the axial side of said flange to admit intercepted oil to the cylinders, a piston mounted for reciprocation in each cylinder, a member mounted for revolution in said casing eccentrically of said hub and connected to said pistons to ing an arm rigidly associated therewith, is

cause reciprocation thereof and means journalled in the hub for causing revolution of the member.

5. A compressor comprising in combination, a casing, a hub projecting inwardly thereof having inlet and outlet grooves and inlet and outlet passages inl communication therewith, a member journalled upon said hub carrying a plurality of cylinders, each cylinder having a port adapted to be placed in communication in turn with'said grooves upon revolution of the member, means journalled in the hub i'or causing revolution of the member, means journalled upon a wall of the casing eccentrically of said hubfhavtons mounted for reciprocation in the cy inders, one of said pistons connected to said rigidly associated means, a link pivotally connected t'o said eccentric means corresponding'to each of the remaining pistons, each of said pivoted means conneced to one .of said remaining pistons whereby revolution of the member will cause `reciprocation of the pistons in the cylinders and the axial relation of said pistons to the eccentric mem# ber will be preserved by said rigid means.

6. A compressor comprising in combination, a gas-tight casing, having a hub proiecling inwardly thereof said hub having inet and outlet grooves and inlet and outlet passages in communication therewith, a

member journalled upon said hub within the casing having a plurality of cylinders, each cylinder having a port adapted to be placed in communication with said grooves in turn as the member revolves, means journalled in the hub for 'causing revolution of the member, a piston mounted for reciproca,` tion in each of said cylinders, a stub shaft mounted upon the wall of the easing opposite said huh-carrying wall and eccentric of said hub, a dise journalled upon said stub shaft within the casing, an arm rigidly carried by said disc connected to one of said pistons, links pivotally connected-to said disc, one of said links connected to each. of the remaining pistons, whereby revolution of the member will cause reeiprocation of the pistons in the cylinders and the axial relation of the istons to the discs will be preserved by sai rigid arms.

7. A compressor comprising in combination, a gas-tight casin comprisin an annular ring and side Wal s secured tiereto, one of said side walls bearing an inwardly projecting hub, a member journalled upon said hub for revolution in the casing carrying a cylinder, a shaft, bushings at opposite ends of said hub journalling said shaft in said hub, a portion of the shaft in spaced relation to the interior of the hub, means carried by the shaft for causing revolution of the member, a piston mounted for reciprocation in the cylinderjmeans in the casing eccentrically related to said shaft connected to said piston to cause reciprocation thereof upon revolution of the member, said shaft having a circumferential groove upon its surface within said space, means for sup lying heavy lubricant under pressure to sai space whereby to cause the lubricant to protrude into said groove to seal the surface of said shaft against passage of gas therealong.

8. A vcompressor comprising in combination, a gas-tight casing having aside wall yand an annular wall integral therewith, a.

hub projecting through said side wall into said casing having inlet and outlet grooves and inlet and outlet passages in communication therewith, a. member carrying a cylinder and mounted for revolution upon said hub, said cylinder oHset with respect to said groove and having a port offset with respect to the axis thereof adapted to come into communication with said groove in turn upon revolution of the member, a side wall associaied with said annular wall in gastight relation thereto, a piston mounted for reciprocation in said cylinder, means to prevent revolution of the piston in the cylinder, means journalled upon said last named side wall eccentrically of said hub and connected -to said piston whereby to cause reciprocation of the piston upon revolution of the member, means journalled in the hub to cause revolution of the member.

JOSEPH B. MCMULLEN. 

